95-733 Internet Technologies      September 27, 2016

Project 3                         Edgent                                   

Due: 11:59 PM, Thursday October 13, 2016

Part 1. Installing Apache Edgent     20 Points
==============================================

	Apache Edgent is an API and runtime designed by IBM for edge analytics.
Your first task is to download and install Apache Edgent from the Apache Edgent
web site: http://edgent.incubator.apache.org. The original download will come
with a build.xml file. In the same directory as build.xml, run the ant command.
This will execute the code in the build.xml file. You may need to first install 
ant. Apache ant may be found here: https://ant.apache.org/bindownload.cgi. There 
is Javadoc documentation available here: 

http://edgent.incubator.apache.org/javadoc/latest/index.html.

	There is sample code available. One of the sample programs consists of a 
temperature sensor (TempSensor.java) and it is designed to generate
temperature values whenever its get method is called. In effect, it acts as an
Edgent Supplier - supplying an infinite stream of Java Doubles. Another file 
is called TempSensorApplication.java. This file illustrates the filtering 
of a stream to create a new stream. The temperature values are filtered and
only those outside of the range [50..80] are placed in the new stream.

	In Part 1, your task is to get this system running. You will need to import
the appropriate jar files into Netbeans (right click the project, select properties
and library and add jar files to the compile time library.)  



Part 2. Modifying the TempSensorApplication   20 Points
=======================================================

	Modify your program in part 1 so that it reports on all values that
are greater than 70 or less than 60. Modify it so that it only polls the 
sensor once every 0.5 seconds. 

	Add a new stream that reads each value in the filtered stream and generates
a JSON string in a Schema.org, JSON-LD format. You may use, for example:

    {"@context": "http://schema.org/",
     "@type": "Sensor",
     "temperature": " 59.84095121646695,
     "units": "fahrenheit",
     "url": "http://www.sensorInfo.com/1234“
     } 


Part 3. Generate the JSON to an MQTT provider  20 points
=========================================================

	Browse the documentation and help files at 
http://edgent.incubator.apache.org. Learn how to generate output
to a remote MQTT implementation. As we did in Project 2, you may use 
a local MQTT provider (Mosquito) or a service on the cloud (HiveMQ).
The necessary jar files are found in the installation directories
of Edgent.

        Modify your program in Part 2 so that it publishes the JSON 
messages to MQTT.

Part 4. Subscribe to the MQTT service with Javascript and Websockets 20 Points
==============================================================================

	Build a simple browser based application that reads the data 
being published to MQTT by Edgent. 

       Show the JSON-LD strings as they change. 

Part 5. Documentation    20 Points
==================================

	There are four programming parts to this project (worth 80 points). The 
last 20 points will be earned by thoroughly documenting your four solutions. 
The grader will be looking to see how well you explain the code each part of the system
you are building. It is OK to include notes from the web (and from the Javadoc)
in your documentation. But the grader will assess the overall quality of these 
comments as well as their careful placement within your code. That is, are the
comments found appropriate to the code being explained? Do the comments help 
or hinder the reader in understanding this part of the project? 

	The documentation should be solid. It should be well written or well selected. 
It should show that the student has a clear understanding of the four parts of Project 3.

















//================================ TempSensor.java =======================
import java.util.Random;

import org.apache.edgent.function.Supplier;

/**
 * Every time get() is called, TempSensor generates a temperature reading.
 */
public class TempSensor implements Supplier<Double> {
    double currentTemp = 65.0;
    Random rand;

    TempSensor(){
        rand = new Random();
    }

    @Override
    public Double get() {
        // Change the current temperature some random amount
        double newTemp = rand.nextGaussian() + currentTemp;
        currentTemp = newTemp;
        return currentTemp;
    }
}




import java.util.concurrent.TimeUnit;

import org.apache.edgent.providers.direct.DirectProvider;
import org.apache.edgent.topology.TStream;
import org.apache.edgent.topology.Topology;

public class TempSensorApplication {
    public static void main(String[] args) throws Exception {
        TempSensor sensor = new TempSensor();
        DirectProvider dp = new DirectProvider();
        Topology topology = dp.newTopology();
        TStream<Double> tempReadings = topology.poll(sensor, 1, TimeUnit.MILLISECONDS);
        TStream<Double> filteredReadings = tempReadings.filter(reading -> reading < 50 || reading > 80);
        filteredReadings.print();
        dp.submit(topology);
        
    }
}